James Murdoch has given up another directorship. He will not seek re-election to the board of auction house Sotheby's, according to a filing with the Securities and Exchange Commission (SEC). The statement says that Murdoch informed the board on 14 March of his intention explaining that it will enable him "to focus on his core responsibilities" as deputy chief operating officer of News Corp. Rupert Murdoch's youngest son was a Sotheby's director for two years. His move follows demands for Murdoch's resignation from some Sotheby's shareholders in the wake of the phone hacking scandal. James Murdoch, 39, resigned from the board of GlaxoSmithKline in January and he also resigned as executive chairman of News International last month. But he remains non-executive chairman of BSkyB - at least, for the moment.